TABLE 2.

Compiled PCR results of autochthonous strains of S. flexneri^a

Expected serotype	No. of strains tested	No. of strains positive by gene for gene with multiplex PCR									No. of strains positive for wzx6 with Sf6 PCR	Serotype result (n)	Differences between serology and PCR
		wzx1-5	gtrI	gtrII	oac	gtrIV	gtrV	gtrIC	gtrX	opt
1a	11	11	11	0	4(1)	0	0	0	0	0	0	1a (7)/1b (4)(1)	(1) 4 strains FG6 (−) and oac (+)
1b	35	35	35	0	35	0	0	0	0	0	0	1b (35)	No difference
2a	58	58	0	58	0	0	0	0	0	0	0	2a (58)	No difference
2b	25	25	0	25	0	0	0	0	25	0	0	2b (25)	No difference
3a	36	36	0	0	36	0	0	0	36	0	0	3a (36)	No difference
3b	8	8	0	0	8	0	0	0	0	0	0	3b (8)	No difference
4a	2	2	0	0	0	2	0	0	0	0	0	4a (2)	No difference
4b	2	2	0	0	0	2	2	0	0	0	0	4b (2)	No difference
4av	5	5	0	0	0	5	0	0	0	5	0	4av (5)	No difference
5a	2	2	0	0	1(2)	0	2	0	0	0	0	5a (1), untypeable (1)(2)	(2) 1 strain FG6 (−) and oac (+)
5b	6	6	0	0	6(3)	0	6	0	3(4)	0	0	Untypeable (6)(3)	(3) 6 strains FG6 (−) and oac (+); (4) 3 strains FG7,8 (+) and gtrX (−)
6	33	0	0	0	0	0	0	0	0	0	33	6 (33)	No difference
7a (1c)	31	31	31	0	0	0	0	31	0	0	0	7a (31)	No difference
7b	2	2	2	0	2	0	0	2	0	0	0	7b (2)	No difference
X	10	10	0	0	0	0	0	0	10	0	0	X (10)	No difference
Xv	7	7	0	0	0	0	0	0	7	7	0	Xv (7)	No difference
Y	6	6	0	2(5)	0	0	0	0	0	0	0	Y (4)/2a (2)	(5) 2 strains type II (−) and gtrII (+)

^a(+), positive result; (−), negative result. The superscript numbers in parentheses are defined in the far right column.